Mike Tuke’s

THERMAL METAMORPHISM

www.earth-science-activities.co.uk

Thermal metamorphism Thermal gradient  D To get students to discus how size of intrusion might affect the thermal gradient show them a piece of toast toasted on one side only on a toasting fork. Students are asked why one needs a toasting fork at a camp fire and why a small fire and not a large bonfire is needed to make toast. Andalusite slate   A P F 30 min This activity is to show that the there is no alignment to the andalusite crystals in slate that has been thermally metamorphosed.  Students measure the orientation of andalusite crystals on a slab of andalusite slate and plot them on a rose diagram and then comment.  Metamorphic aureole E P F 60 min To determine how the temperature varies with time and distance from the intrusion and to see the effect of the size of the intrusion. Boiling water is poured into a tin which is in the centre of a larger sand filled tin. Thermometers are placed in the sand at various distances from the central tin.  Students record the temperatures every 2 min.  Inner tins of different sizes can be used and the sand can be damp or dry.